BACKGROUND: Survivors of cancers diagnosed during adolescence and young adulthood (AYA) represent a distinct group of survivors who are vulnerable to experiencing chronic stress and adverse health outcomes.1 Receiving a cancer diagnosis during a developmental period marked by peak socioemotional and physical changes has the potential to exacerbate typical adjustment problems and interfere with important age-specific milestones; despite their vulnerability, there are a lack of targeted programs to help AYAs manage these stressors. Using self-report and objective measures, this study proposes to develop and test the feasibility, acceptability and preliminary effects of an adapted, virtually delivered, evidence-based program, the Relaxation Response Resiliency Program (3RP),9 in promoting stress management and coping among survivors of AYA cancers. Specific Aims: Using a 2-phase, mixed methods approach,60 we propose to 1) adapt a mind-body resiliency group intervention for AYAs (3RP-AYA) that is aimed at reducing stress and promoting stress- management during the post-treatment transitional period; 2) conduct an open pilot (n=8) to test and refine the 3RP-AYA; 3a) examine, in a pilot randomized controlled trial (n=60), the feasibility, acceptability, and preliminary effects of a virtual, group-based, stress-management program for AYAs who are in the early stages of survivorship; and 3b) explore the feasibility and acceptability of collecting hair samples to examine intervention-related changes in stress as measured by cortisol. CANDIDATE: Dr. Perez is a Hispanic female childhood cancer survivor who is an instructor at the Massachusetts General Hospital/Harvard Medical School. This proposal will provide Dr. Perez with the requisite skills and mentored training she needs to fulfill her career goals of becoming an independent investigator with expertise in designing, testing, and disseminating innovative, integrative (i.e., combined behavioral and mind-body skills) interventions to improve physical and mental health outcomes among cancer survivors. MENTORING: To support her career goals, Dr. Perez has assembled a successful group of esteemed faculty with expertise in mixed methods and mind-body research (Elyse Park, PhD, MPH), behavioral intervention technology, behavioral science and research dissemination (Joseph Greer, PhD), cancer survivorship (Christopher Recklitis, PhD, MPH, Jeffrey Peppercorn, MD, MPH), stress and psychoneuroimmunology (PNI; John Denninger, MD, PhD), and biostatistics (Yuchiao Chang, PhD). TRAINING: Through the mentorship support, resource-rich environment, didactic training, and research activities afforded by this award, Dr. Perez will achieve the following training aims: 1) To develop expertise in designing and testing targeted integrative interventions for survivors of AYA cancer; 2) To acquire skills in the use of behavioral intervention technologies (BITs) as a platform to deliver and disseminate behavioral interventions for AYAs; and 3) To develop competence in PNI research within cancer survivorship.